Automatic bed leveling (ABL) relies on Z height readings from hardware that is interpreted by a compatible firmware for the 3D printer, ie no more fiddling with wingnuts and screwdrivers. The Ender 5 has a manual bed leveling process where you move the hot end around the bed and use a piece of paper to space it properly while you adjust the bed height knobs. Even with ABL you will still perform this process to tune the printer as close as humanly possible. Where ABL comes in handy is that it will use a probe to very precisely measure the leveling error across your print surface which can include defects on the bed or just poor calibration (human error) of the manual tuning knobs. The process then uses software to compensate for leveling error automatically by probing the surface in a grid pattern prior to each print and storing the compensation results in memory. Your prints come out better and you spend very little time messing with the manual adjustments. Ok, so we know we need this feature. Now lets add it to the ender 5.
BL-Touch Automatic Bed Leveling
Several ABL sensors exist but one of the most common is the BL-Touch sensor. I opted to go this route and fortunately for me the Ender 5 has a BL-Touch upgrade kit and firmware to make the process very easy available on Amazon and linked below.
Note that the BL Touch has a view different versions. The link above gave me the v3.1 version which is the latest as of 2020. The version will dictate firmware settings so be aware of which version you have.
Installing the BL-Touch
3D Printing Canada has a fantastic youtube channel and they happened to have a video specific to the Ender 5. With this tutorial the install was pretty straight forward.
OK, with bed leveling in place now I wanted a few more features: